ittnashfandomcom-20200213-history
IT250 - Jun '09/Week 2
Pre-Notes Always log in as a regular user, NOT as the root user. GNOME is the default desktop GUI Operating system makers do not make desktops, desktop makers do not make operating systems, this is why there is X. X allows you to use whichever desktop with which ever operating system you please. Server operators don't load the gui. (Why?) because you don't need them, you can save the cpu cycles and RAM without it. They use the command line interface listed above. Linux Facts In Linux, everything is open source. If you have it, you can use it. People that sell Linux only sell their help and support. Linux can read in NTFS, not write. Microsoft will not read linux based files. SAMBA will allow them to work together. GNOME is more mac look 'n feel KDE is more Vista oriented Virtually, no one writes viruses for linux. Reason is, hardly anyone uses Linux desktops, so what the point of attacking them? Open Office Open Office.org is the open source answer to Microsoft Office. You can open MS office files within it and edit them. There is a push worldwide to establish a single document file type that anyone creating files will go by these standards. Microsoft hates this. They are fighting it completely to make sure it isn't established. (Microsoft Internet Explorer is not included in the EURO version, instead you have toinstall it manually.) Run Levels, Again! Run level 1 - You must be sitting at the computer to user level 1. This is maintenence mode. No network support, only one user, fail safe. 2 and 4 - User defined, you can do anything you want to with them Run Level 3 - Server Mode. No GUI, you and the network. Run Level 5 - Desktop Configuration. You could run a server here, but also have a GUI. This is default run level for Fedora. Run Level 6 - Reboot. INIT as INIT starts, it wants to know your run level. (/ETC/INITTAB) The last line in it tells you is your run level. (Inside a configuration file, the # sign means it is a documentation file, it is not read. ) /ETC/RC.D /ETC/RC.D/RC0.D, ....RC1.D, RC2.D These are startup and shutdown scripts, for every run level, there is a script. (if I want run level 5, it will run srcipt RC5.D, get it?) All startup scripts start with S All shutdown scripts start with K (means kill) Dual Boot There once was another bootloader for Linux, LILO, it was the original, but grub was favored because it dual booted and ran off of configuration files. LILO is an executable file and must be changed everytime. *LILO can now dual boot. Permissions - means it is a fie. D means it is a directory. $ CHMOD is a command to change permissions. Now, I want groups to have write permissions $CHMOD G+W File1 (This will now give permission to write to the group.) I want to remove read permissions from everyone $CHMOD O-R File1 I Want to give Everyone the Execute Permission. $CHMOD UGO+X File1 I want to remove all permission from group and other. $CHMOD GO-RWX File1 Numerics First, Let's understand the numeric value. Read - 4, Write - 2, Execute - 1 If you add these values together, you can gain certain permissions. The numeric layout to the right shows what each number allows for permissions. Example: 6 would give the read and write permissions. Example: 1 would give the execute permission, geti it? NOW, let's look at it in a command line. $CHMOD 713 File1 The 7 gives USERS read, write, and execute The 1 gives GROUPS execute The 3 gives OTHER write and execute Think about it like this ($CHMOD UGO File1) now, replace the U, G, and O with numeric permissions for each division. $CHMOD 704 File1 To get the answer, highlight the area to the right of the question. The 7 gives _____ read, write, execute. Users The 4 gives _____ read. Other The 0 gives _____ nothing. Groups VI Editor to open a file in VI: vi file1 At the bottom of the picture is the word insert. Insert - you can insert typing wherever your flashing cursor resides. (to exit insert mode, hit esc) Replace - will replace any text that you come across. Save :wq! (w for write, q for quit, ! for no error reports) :w (saves without exiting) Copy : w file2 (this saves the file as a new file wth a different name, ie:file2) Homework http://images3.wikia.nocookie.net/ittnash/images/6/61/Homework_Week_2.pdf Homework Week 2